Originally Posted by cgalpin
Sadly replacing the fuel pump has not solved it. The sad story goes something like this
1. Ponied up for replacing the complete pump assembly as I managed to twist one of the steel pipes coming out of the pump disconnecting the rusting connectors. Got a great deal from George at rovers down south though.
2. After installation, the telltale lighting issues of this problem where still there.
3. I futzed around a bit, not really changing anything, but running it for a while with the battery diconnected, the "problem" went away.
4. I started reconnecting everything bit by bit and eventually hooked up the battery again and still the problem was gone. Even stopped and started it a few times and it was running great.
5. Being foolish enough to think it might be solved I headed out for a test drive (in the snow) and went well until it broke down pulling into a gas station a mile from home. It died while braking, exactly the same problem as before, and the light problem was back.
At that time the fuel pump was not pumping! I got a tow home (btw, don't ever try get your wife to tow you home in the snow uphill..)
At home the light problem was still there, but the I could hear the pump. Right now it won't start, has the same "no fuel" symptoms as before (despite the pump working) so I'll replace the fuel filter once I get a hand pushing the POS into the garage. Too damn cold out there.
Sucks to be me.
What do you guys think:
- when you turn the ignition key in to start the truck, the fuel pump relay kicks in, instead of hearing a strong fuel pump noise, you hear a weak noise and the stop lights turn on.
- the lights turn off as soon as the fuel pump relay turns off.
- if you hit the brakes, the engine dies.
Here is my take: the fuel pump ground wire is not going to the ground instead, it is connected/touching the 12V input of the stop lights. Because the fuel pump and the lights are connected to each other, the fuel pump does not have the full 12V (i.e. two resistors => voltage split).
This also explain that if you hit the breaks, the fuel pump stops (because then it gets 12V on both sides).
Now.... How to we find where those wires are touching? Looks like there is a long piece of wire that goes through the chassis and no connector we can unplug..... Any way to troubleshoot this without cutting wires?